Insulated electric conductor



July 23, 1935.

R. A.. SCHATZEL INSULATED ELECTRIC CONDUCTOR Filed May 22, 1951.

u M M TORNEY/ Ptented `Iuly 23, 1935 PATENT oFFlhcE INSULATED ELL'CTRICCONDUCTOR Rudolph A. Schatzev'l, Rome, N. vY., assignor to General CableCorporation, New York,y N. Y., a corporation of New` Jersey ApplicationMay 22, 1931, Serial No. 539,238

17 Claims.

duct'ors and more particularly to theV type commonly known as code wire,a term applied to.

rubber insulated wire which complies with the requirements of theNational Electrical Code.

Under such requirements, it comprises an insup lating cover of rubberover the metal/lic conductor and av surrounding protective braid whichmay be in one or `more layers depending upon the particular use to whichthe conductor is to be put. It `will be readily apparent that such wireis highly inammable, but is now usually rendered name-resistant bysaturating the protective. cover or braid with a name-proof saturantSuch, for example, as stearin pitch, asphalt or some similar material.Such coated wire, however, is not satisfactory as the coating is stickyand untidy, conductors so made are nor-V mally black in color, andefforts to provide distinctive colors for diierent conductors of thistype have notrbeen satisfactory.

For some time there has been a demand for flame-proof code wire. havingvariously colored surfaces .to permit readyv identification of differentconductors, but this demand has never,

to my knowledge, been satisfactorily iilled due to the difficulty ofproviding a coloring material which would properly cover the name-proofsaturant and provide the necessary color. Ordinary paint can not beapplied because pitch or asphalt are readily soluble in the paintvehicle, and so produce .discoloration of the paint .'surface. Whilethis might be overcome by a plurality of coats, such a process is tooimpractical and costly from a manufacturing point of view forconsideration.

'An object of, this invention is to provide a. lflame-proof, insulatedconductor of the type set forth constructed and arranged to have itssur- 40 face 'of any desired color for identification or other purposes.f

A further object is to provide a flame-proof colored code wire togetherwith a method of making the same.

These and other objects which will be apparent to those skilled in thisparticular art are accomplished by means of the present invention. YInthe accompanying drawing, u

The single ligure shows an insulated conductor Y constructed inaccordance with one embodiment of this invention, the respective layersbeing successively removed for purposes of illustration.

In carrying out the present invention, an electrical conductor 5 isprovided with the usual insulation '6 of rubber or the like, and aprotective This invention relates to insulated electric con-A braid 1 isformed around the rubber insulation. Preferably, the conductor isrendered name-resistantby impregnating the braid with a iiameresistantsaturant such as stearn pitch, asphalt or some similar materialindicated at 8 inthe 5 figure.a Y

In the present invention, the flame-proofing material is covered andprovided with a distinctive color by applying to the surface thereof alayer of material 9 which is not only capable of complet-ely coveringthe pitch or the like in a single coating so as to form anv opaquelayer, but which is also capable of forming a base for a distinctivecolor I0 which can either be applied to the coating after the coating isin place or, under certain conditions, be embodied in the coating beforeit is applied over the pitch. I have foundthat materials which can beprovided in the form of nely subdivided thin metallic flakes, such asthe so-called bronze powders, will completely cover the pitch surfaceand when applied in accordance with the present invention provide aiirmly adherent opaque layer which is especially satisfactory as a basefor a color coating or, if desired, the flake can be previously col- 25ored or dyed so that it will itself produce the desired color on theconductor when applied over the pitch. y

A good example of a suitable material is aluminum in the form knowntothe trade as aluminum ake although other material such, for example,as iron oxide pigment and those materials known generally as bronzepowders are equally satisfactory. Such a pigment not only completelycovers the pitch saturant in a single 35 coating, but forms aparticularly advantageous base or surface to which any suitable pigmentcan be applied or, if desired, the metallic ake material itself can bedyed or otherwise colored prior to its application to the conductor. 40

The coating of covering material can be applied to the conductor invarious ways. One satisfactory way is to pass the pitch coated conductorthrough a suspension of the ake material in a suitable vehicle such as avarnish or 45 lacquer. If some color other than the natural color of thecovering material is desired on the 'finished conductor, this can beeasily accomtaining a colored aluminum .uspensiom for ex- 55 ample, isby grinding aluminum flake and the desired pigment together, in whichoperation the aluminum flake takes up( enough of the pigmentl to producethe required color. The colored aluminum flake is then suspended in asuitable vehicle and the pitch coated conductor drawn through it so thatthe colored aluminumis deposited thereon to'form the desired coatingover the pitch and to give the desired color. If a slipperyv finish isdesired, a thin coat of rparaffin or other wax canbe wiped on thecolored conductor in the manner well known in the art. If some bronzeother than aluminum flake is employed as the covering material, it canbe colored and applied in the same way.

Instead of coloring the aluminum or other metallic flake prior to theapplication thereof to the conductor, the conductor can be provided witha coating of uncolored material which will form a base over which anysuitable paint or quick drying colored lacquer or varnish' can beapplied. In this case the coloring material can be either a pigmentedlacquer-or varnish or a dyed material. Ordinarily, pigments have greatercovering power and require fewer coats. 'I'he metallic flake which isapplied over the conductor provides an opaque cover foi the name-proofsaturant on` which the suitable coloring materials can be placed.

A suitable aluminum paint for carrying out the present process can bemade, for example, with the following ingredientsz- Percent by weightChina-wood oil 20.8

Cumar resin (varnish grade) 18.2 Manganese linoleate 2.1 High flashnaphtha 6.8 Turpentine 6.8 Gasoline 3.6 Textile spirits '20.8 Varnishgrade aluminum flake 17.3

I have also found that the metallic bronze powder can be applied to theconductor without providing a liquid vehicle therefor. In this case, thepitch covered conductor is run through a die while hot, and thendirectly through a container of either plain or colored metallic powder.The material adheres to the conductor and is wiped on to produce asmooth even surface and the covered wire may or may not be passedthrough a suitable size or lacquer to provide a smooth surface. Inapplying ythe lbronze powder in the dry form, it will sometimes be founddesirable to pass the pitch coated conductor through a lacquer solventprior to passing it through the metallic powder, and then again wipingthe coated wire with the solvent after the aluminum or other bronze hasbeen applied thereto. This will materially increasev the uniformity vofthe coating and its adherence to the pitch when the dry powder isemployed.V A paraliin coating may be applied at the same .time bysaturating the solvent with paraffin.

Instead of using metallic flake or bronzepowder for covering thename-proof saturant, the latter can be covered by a layer of size boundon with mica which also provides a surface to which any desired colorcanbe applied, which is unaffected by such solvents as are employed inlacquers or other coloring mediums andwhich protects the pitch or thelike against such solvents. For example, the pitch coated conductor canbe passed through a sizing bath formed by a water solution of a suitablesizing material.

The water does not aiect the waterproof saturant and the size, when dryand hardened, with the mica binder completely covers the vsaturant toform a surface which can be colored by any suitable material, and thecolored cable finished with any type of wax, parain, or other surfacedesired.

A suitable size can be made, for example, from the following ingredientsCorn starch lbs. 5 Pulverized glue oz. 11/2 Japan wax oz. 3 Zincchloride oz. l Copper sulphate oz. 1 Water (hot) gallons If desired, thewax can be omitted.

minous flame-resistant compound, coating said compound with a layer ofdry metallic flake and wiping the coated conductor with a lacquersolvent. 4. The process which comprises coating an insulated conductorwith dry aluminum flake and wiping' the coated conductor with a lacquersolvent.

5. The process which comprises providing an insulated conductor with aprotective cover, impregnating said cover with a flame-resistantsaturant, applying an aluminum coating to the saturated cover and wipingsaid conductor with lac- Aquer solvent before andafter the applicationof I aluminum thereto.

6. An insulated electric cable having a fibrous cover .impregnated withflame-.resistant pitch and surrounded by a coating of aluminum flake.

'1. An insulated electric cable having a fibrous cover impregnated withname-resistant pitch and surrounded by a coating of colored aluminumflake.

8. An insulated wire having dark sticky flame resistant materialimpregnatingthe insulation thereof, a powdery material disposed directlyupon the dark sticky flame resistant material, and a separate thin lightcolored coating layer disposed directly upon the powdery material, saidthin light colored coating being of a character which tends to blendwith the dark sticky flame resistant material with attendantdiscoloration of the thin light colored coating and the powdery materialserving to prevent such blending and discoloration of the superimposedthin light colored coating.

9. An insulated wire having dark sticky flameresistant materialimpregnating the insulation thereof, a metallic powdery materialdisposed diposed directly upon the powdery material, said coloredcoating being of a character which tends rectly upon the dark stickyname-resistant material, and a separate colored coating layer disambosto blend with the dark sticky name-resistant material with attendantdiscoloration, and the powdery material serving to prevent such blendingand discoloration of the superimposed colored coating.

10. A'n insulated wire having dark sticky flameresistant materialimpregnating the insulation .f thereof, a layer of size disposeddirectly upon the directly upon the layer of size and mica, said col--dark sticky flame-resistant material, and a separate colored coatinglayer disposed directly upon the layer of size, said colored coating-being of a character which tends to blend with the dark stickyflame-resistant material with attendant discoloration, and the sizeserving to prevent such blending and. discoloration of the superimposedcolored coating.

ll. An insulated wire having dark sticky flamer'esistant materialimpregnating the insulation thereof, a layer of size and mica disposeddirectly upon the dark sticky name-resistant material, and a separatecolored coating layer disposed ored coating being oi a character whichtends to blend with the dark sticky flame-resistant material withattendant discoloration, and the size and mica. serving to prevent suchblending and discoloration of the superimposed colored coating.

12. An insulated wire having dark sticky flameresistant materialimpregnating the insulation thereof, a layer of aluminum flake disposeddirectly upon the dark sticky flame-resistant material, and a separatecolored coating layer disposed directly upon the aluminum ilake, saidcolored coating being of a character which tends to blend with the darksticky flame-resistant material with attendant discoloration, and thelayer of aluminum ake serving to prevent such blending and discolorationof the superimposed colored coating.

13. The process of producing a colored flameresistant insulated electricconductor which com- 'prises covering an insulated wire with stearinYpitch, providing a coating of size and mica over said pitch, andcovering said coating of size with a coloring material. e

14. The process of producing a colored llameresistant electric conductorwhich comprises cov- Y ering an insolated wire with stearin pitch,providing a coating of metallic aluminum flake oversaid pitch andcovering said aluminum flake with a coloring material'. I 1 15. Aninsulated wire having a bituminous name-resistant material impregnatingthe insulation thereof, a sealing layer of exible size surrounding saidbituminous layer and joined to said layer'by mica, and a coating oflacquer surround- ,ing said mica and size and protected thereby' againstblending with and discoloration by the bituminous material.

' 16. The process of producing ta colored flameresistant insulatedelectric conductor which comprises covering an insulated wire with abituminous flame-resistant material, applying over the bituminousmaterial a coating of material insoluble in paint and lacquer solvents,and applying over said coating a layer of colored lacquer which isprotected by the intervening coating against blending with anddiscoloration by the bituminous material.

1'7. 'An insulated electric conductor comprising a bituminousname-resistant material impregnating the insulation thereof, a coatingof material insoluble in paint and lacquer solvents surrounding saidflame-resistant material, and an outer layer of colored lacquer which isprotected by the intervening coating against blending with anddiscoloration by the bituminous material.

RUDOLPH A. SCHA'IZIEII...`

